It is known that vehicles may be equipped with speed control systems, such as, for example, on-road cruise control systems, that allow a user to define a desired set-speed and then maintain the speed of the vehicle at that particular set-speed. In very simplistic terms, this may be accomplished by sending commands to the powertrain and/or braking subsystems of the vehicle, for example. While such systems have any number of benefits ranging from wear on the vehicle to driver comfort, they are not without their drawbacks or disadvantages.
For example, one drawback of conventional systems is that they often have an operational limit as it relates to the amount of powertrain output torque that the system may command or request from the powertrain subsystem when the system is active or in use. More particularly, when the speed control system is in use, a default maximum torque limit is established, which is typically a fixed proportion of the maximum torque capacity of the powertrain subsystem, and the speed control system is not permitted to request or command torque that exceeds this torque limit. At least one reason for imposing such a limit is to ensure compliance with specific regulations concerning the use of speed control systems on the road, and the rate of acceleration that the speed control systems may command during operation on the road. However, these artificially imposed torque limits may limit off-road capability of the vehicle, and the speed control system, in particular.
Accordingly, there is a need for a speed control system and a method for use with the same that minimizes and/or eliminates one or more of the above-identified deficiencies.